Flexible part carrier strips for holding and transporting pre-formed parts are commonly employed in the automated manufacture of electronic and other components. Many electronic components are manufactured using robotic loaders and other automated assembly devices in order to maximize the efficiency of the production line. Automated assembly machines typically have a loading arm which retrieves the part from a pre-designated location and inserts the part in place on a component being assembled on the production line, such as an electronic circuit board. The part is then soldered, welded, or otherwise connected to the circuit board by another automated step further down the assembly line. Such automated assembly devices are commonly used in the construction of electronic circuit boards.
In order to maintain the efficiency of the production line, the component parts must be presented to the automated loader at a consistent pre-determined location, and at a consistent pre-determined orientation. Any deviations from the desired orientation or location will result in defective assembly of the final product. In order to ensure the proper presentation of the part to the loading device, most automated assembly lines utilize carrier strips, carrier tapes, or carrier trays to deliver a properly oriented part to the pickup point.
On a typical carrier tape or strip, the oriented parts are secured at precise intervals along a flexible continuous strip of plastic. The steps of forming the part and securing the part to the carrier strip is usually performed away from the automated assembly line. The strip holding the parts is then rolled, transported, and fed into a loading machine on the assembly line using a commercially available feeding device. For example, one type of carrier strip known under the tradename "GPAX" is described in U.S. Pat. Nos. 4,583,641 and 4,757,895. The GPAX structures disclose a carrier tape having a plurality of part receiving recesses and intervening slots punched along the length of the strip. The holes are adapted to engage legs, stubs, or leads on the part in order to ensure proper and secure positioning of the part on the tape. A plastic bonding tape which overlays the parts is pressed or stitched onto the carrier tape between adjacent parts in order to secure the parts in their respective recesses. However, many electrical parts are stamped from thin sheets of metal and hence are flat and very delicate.
Another carrier strip structure, known as "debossed tape and reel" consists of a plastic carrier tape with a plurality of recesses or pockets along the length thereof in which the parts are placed. A sealing tape is bonded over the length of the carrier tape in order to retain the parts within their respective pockets. The carrier tape is fed into the robotic loader, which peels away the sealing tape, removes the part, and then discharges both the carrier tape and the sealing tape to waste. Although the debossed tape and reel structure is better suited for flat parts than the GPAX type structure outlined above, and the two-part disposable nature of the tape and reel method is very expensive frequently requires human insertion of the parts into the recesses. Accordingly, there exists need for an improved and more economical flexible carrier tape which is well-suited for securing and transporting flat parts, and which is readily adaptable to automated loading and unloading.